1. Field of the Invention
The claimed invention generally relates to image forming and, more particularly, to an image forming apparatus employing an electrophotographic system or an electrostatic recording system, such as a copying machine and a printer.
2. Description of the Related Art
To apply various types of recording materials particularly thin paper, a certain configuration is provided with a conveyance belt for conveying a recording material and transfers a toner image from an image bearing member onto a recording material conveyed by the conveyance belt. However, since the toner image is electrostatically transferred from the image bearing member onto the conveyance belt, the recording material after the toner image transfer electrostatically adheres to the conveyance belt. In order to convey the recording material after the toner image transfer toward a fixing unit for fixing the toner image, a unit is used for detaching the recording material from the conveyance belt. As a conventional unit for detaching a recording material after the toner image transfer from a conveyance belt, Japanese Patent Application Laid-Open No. 2011-95368 discusses the use of a separation roller for stretching the conveyance belt to detach the recording material therefrom.
However, if there is no intermediary between the rear surface of the recording material and the conveyance belt, a space hardly occurs therebetween and accordingly the rear surface of the recording material is likely to be firmly attached to the conveyance belt. As a result, even when the leading edge of the recording material after the toner image transfer reaches the position of the separation roller, the recording material may not be detached from the conveyance belt. Meanwhile, if toner is transferred onto the conveyance belt, the toner between the rear surface of the leading edge of the recording material and the conveyance belt serves as an intermediary for weakening the adhesiveness between the recording material and the conveyance belt. However, if toner is transferred onto the entire surface of the conveyance belt, the toner can prevent the rear surface of the recording material from firmly adhering to the conveyance belt but may cause another issue that the conveyance belt is excessively smeared. Accordingly, there is a need for a method for suppressing the adhesiveness between the rear surface of the leading edge of the recording material and the conveyance belt because of no intermediary therebetween, without excessively smearing the conveyance belt with a simple configuration.